Sarcophyton
is a genus of soft corals in the Family Alcyoniidae.
They are commonly called "leather,"
"toadstool" and "mushroom"
corals. Characterized by a conspicuous stalk
that lacks polyps and a broad and often folded
polyp-bearing upper surface (the capitulum and
polypary, respectively), they are among the
easiest soft corals to identify. Small colonies
do not have a folded polypary. These corals
are dimorphic, and the smaller siphonozooid
polyps appear densely as small dots or depressions
between the feeding polyps (autozooids). The
autozooids are completely retractile, with the
oral disk and tentacles perched atop long stalks
called anthosteles.

Sarcophyton
colonies can grow very large - colonies weighing
over 50 pounds are common in private aquaria.
They can contract dramatically, and the whole
colony can fold sideways or stand erect. The
folding of polypary and colony is likely a reaction
to water flow and to maximize capture of food
particles from the water. Common colors are
shades of brown and tan, yellow, cream and green.
Some beautiful morphs have fluorescent green
tentacles.

They
are zooxanthellate and are extremely easy to
maintain in aquaria. They are among the most
abundant soft corals and are widely distributed
in terms of geography, depth and reef habitat.
Large areas nearly covered in Sarcophyton
colonies are common in soft-bottomed and turbid
nearshore environments, while colonies on oligotrophic
reefs tend to be more solitary, though they
can be numerous. The colonies are broadcast
spawners, but also reproduce asexually by budding
from the base, colony fission or budding from
the edge of the polypary. Asexual reproduction
is more common in those found in turbid and
muddy water. Movement of colonies is also possible
within the tank, and Fabricius and Alderslade
report movement of up 0.5m in a few months.

These corals produce abundant secondary metabolites,
and while they are commonly maintained in tanks
without apparent problems, some species of corals
may be sensitive to these toxic chemicals. In
particular, members of the Family Euphyllidae
seem very sensitive to Sarcophyton. Common
problems of the genus include a "rotting
condition" where open lesions form on the
stalk or, more commonly, on the polypary. This
may be most common when sediments or foods settle
within the colony's depressions and folds. Several
predators are known, including nudibranchs and
snails. Sarcophytons may also periodically
slough a surface layer known as a mucus tunic,
a process during which the colony may look "unhealthy"
with the autozooid polyps failing to extend.
Strong water flow generally helps shorten this
process, and a well-flushed colony seems to
slough a mucus tunic only rarely. Additionally,
many fishes may perch atop the polypary, and
clownfish may even adopt colonies as surrogate
anemones.

Propagation
of Sarcophyton is easy and commonly done.
Simple core punches or snips of the colony,
or complete fragmentation or horizontal to vertical
division of a colony will generally be well
tolerated and result in the reformation of the
adult growth form in short order. However, because
of the toxic chemicals contained in the tissue,
it is not recommended to conduct fragmentation
within the main tank; it should be performed
instead in a container with resulting propagules
well rinsed and flushed prior to returning them
to their culture tank or the main tank. Cut
edges heal quickly by forming a callus, and
placing cut edges into strong water flow facilitates
the process.

These
corals are among the first to be kept in reef
aquaria, and are common in the wild and in the
trade. Their durability and beauty no doubt
are reasons for their continued popularity.

Text
by Eric Borneman.
Many thanks to John Love (Rock Anemone) for
his assistance with this project.